Important information about decking & cladding
1. Tannin staining happens in all external wood products.
2. Tannins in WPC (Wood Plastic Composite) decking are a natural component of the wood fibres used in the composite material. They can cause temporary discoloration or staining, particularly in the initial weathering period, as they leach out with rain and UV exposure. These stains are generally temporary and will fade as the decking is exposed to the elements and undergoes normal weathering.
3. Stains - water stain marks can show on composite deck boards. There are 2 main types of water stains; both of which will generally disappear with exposure to general weathering.
3a. Water stains from wood tannins will occur in the early life of your deck as the natural tannins come out of the wood fibres at the surface of the composite decking. This will happen in the early weeks of your deck being laid, and will depend on how exposed to the elements your deck is before the weathering process is complete. This type of stain can be more prominent when new decking is exposed to direct sunlight in the first few months of its life.
3b. Water stains from water pooling or dripping can happen on composite decking just like it can with many other materials/surfaces such as timber decking, glass, laminated flooring etc. This can leave a “shoreline” effect. The visibility of the stain will be governed by factors such as how dirty the decking is and how quickly the water dries from the water pooling Again, this can be exaggerated in hotter weather. Both types of marks/stains will disappear naturally over time unless, of course, you have a recurring problem that allows water to continually land on the composite decking. E.g. a drip from the gutter will continue to make marks. Oil or cigarette stains etc. can be very difficult to remove from the surface, avoid contact at all times.